It has been postulated that penicillin failures in the treatment of gonorrhea may be the result of conversion of normal cell forms of Neisseria gonorrhoeae to the wall-defective or L-form. The L-form of the gonococcus can continue to exist and reproduce in the presence of penicillin and this may account for chronic infection despite antibiotic therapy. Similar conversions of normal cells to wall-defective forms has been noted in the case of Neisseria meningitidis.
In order to elucidate the role of wall-defective gonococi, it is necessary to secure their in vitro conversion and growth. However, success in this area has not been easy to achieve, although some success has been reported by Roberts in the Journal of Bacteriology, vol. 92, pages 1609-1614 (1966) on a sucrose stabilized medium. Lawson and Douglas have reported in the Canadian Journal of Microbiology, September 1973, (abstracted at 1972 Annual Meeting of the American Society for Microbiology) that PVP stabilized media comprising brain heart infusion broth, agar, horse serum, and penicillin is useful in inducing conversion to the L-form. Also of interest in U.S. Pat. No. 3,669,846, issued June 13, 1972 in class 195/96 for "Process for Obtaining and Preserving Stable Bacterial Variants"; as well as U.S. Pat. No. 3,687,816, issued Aug. 29, 1972 in class 195/100 for "Bacterial Growth Media"; U.S. Pat. No. 3,098,016, issued July 16, 1963 in class 195/102 for "Process for Preparing Sterile Vials Containing Culture Media and a Carbon Dioxide Atmosphere"; U.S. Pat. No. 3,477,914, issued Nov. 11, 1969 in class 195/96 for "Treating Method of Streptococcus Hemolytics and the Preparation Containing the Said Microorganism"; and U.S. Pat. No. 3,527,712, issued Sept. 8, 1970 in class 252/316 for "Dried Agarose Gel, Method of Preparation Thereof, and Production of Aqueous Agarose Gel".